Tag:AsLOV2(T406A.T407A) corresponds to the LOV2 domain of the Avena sativa Phototropin 1 (PT1) gene, including the LOV core domain and C-terminal Jα-helix, mutated to carry T406A and T407A amino acid substitutions. The photoreactive LOV domain interacts with the Jα domain in the dark (the T406A and T407A mutations increase this docking affinity), resulting in a 'closed' conformation, while exposure to blue light leads to conformational changes that result in dissociation and unwinding of the Jα helix (PMID:22388287). This property can be used to regulate the activity of a tagged protein of interest in a light-regulated manner.